Appliance for finishing crank pins



' S. A. NONSUCH. APPLIANCE FOR FINISHING CRANK PINS.

Patented A r. 18, 1922.

APPLICATION FILED DEC-3| I920- a INVENTOR: $010 in #317022 su 0J2,

ATTORNEYS.

UNHTESTATES scrorn a nonsncn, or rnrnannnrnra, rnn'nsvnvnnra.

LIANCE FOR- FDVISHING CRANK PINS.

To all whom it may concern:

Be it known that I, ScIoTA ALBERT NON- sUoH, a citizen of the United States, residing in the city of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Tm- )rovements in Appliances for Finishing Frank-Pins, whereof the following is a specification, reference being had to the accompanying drawings.

My invention relates to appliances for finishing crank-pins, and more especially for refinishing the crank-pins of automobile engines after they have been worn out of shape or their surfaces have been scratched and. damaged in use. With my appliance, the crank-pins of such an engine can be accurately and expeditiously refinished without removing the crank shaft from the engine or otherwise dismantling it,excepting only to the extent of. disconnecting "the connecting rods from the crank-pins to be refinished.

My appliance is simple and rugged in construction and economical to manufacture, be-

sides being convenient, durable, and accurate in use.

Various other advantages of my invention will appear from the description hereinafter of the best embodiment at present known to me, while its scope and essentials in its various phases will be indicated in my claims.

In the drawings, Fig. T is a side elevation of my appliance, showing it mounted for operation on a crank-pin,which appears in cross-section. v Fig. H is an edge elevation from the right of Fig. l.

,Fig. TH shows a cross-section at a plane corresponding to the line TIT-TH in Fig. T.

Fig. TV is an enlarged view illustrating the form and action of the cutting part of the tool employed in the appliance.

Fig. V is a plan view of said cutting part.

Fig. VT is a side elevation illustrating the operation of the appliance on a crank-pin in an engine.

Figs. VH and VTTT are enlarged fragmentary views, partly in section, illustrating the operation of the appliance on different forms of crank-pins.

The form of appliance here illustrated (see Figs. T and H) has a frame structure 1 comprising a massive, rigid yoke 2 open at one side, a massive elongated handle 3 rigid with the yoke 2 extending from one side thereof, and a strong, rigid bridge member i Specification of Letters Patent.

Patented Apn as. fees.

Application filed. December 3, 1920. Serial Ito. 427,939.

ingof the yoke, so as to form a solid tensile connection thereacross when the appliance is 1n use, but is removable from across said opening to permit the introduction of a crank-pin 9 within the yoke. The yoke 2 and the handle 3 are formed of one integral plece of metal, and in outline merge gently into one another. The bridge member 4 is in the form of a U-shaped. stirrup of heavy sheet metal; its ends are pivoted to the front lower corner of the yoke 2 by a pin 5 extending therethrough, and its center carries a set screw 6 that is threaded therethrough and engages in a socket 7 on the front upper corner of the yoke. When the screw 6 is tightened up hard, the member 4 is made firm and rigid across the mouth of the yoke 2. 'The frame structure 1 carries the surfacing tool 10 for refinishing the cylindrical bearing surface of the crank-pin 9, and also bearing means for maintaining the frame and the tool in the proper relation to in substantial conformity to the circular curvature of the crank-pin surfaces that they engage. The bearing surface of the block 11 opposite the toollO extends over a very considerable are or angle (some 150) and is eased, so to speak, by curvature to a radius sufficiently greater than that of the crank-pin surface which it engages to make its ends about one-thousandth of an inch from said surface when itsmiddle is in contact therewith, so as to permit slight variation of the region or line of greatest contact pressure against the cylindrical or curved surface of the crank-pin 9. (ln Fig. l, of course, this difference of curvature, between crank-pin and bearing block 11' is exaggerated in order to make it perceptible.) At its rear,.the bearing block 11 has a flat face (perpendicular to the center line of the tool handle 3) that rests against a corresponding fiat surface on that side of the yoke 2 and is flanked byinclined surfaces that engage correspondingly inclined surfaces on the yoke; it is firmly held or clamped in place by'a headed screw 16 thatextends through the yoke and a threaded hole in the block.

The bearing 12 at the following side of takes into thetool has its bearing surface curved to the radius of the circular crank-pin surface that it engages, and its rear face is shaped to engage the corresponding inside surfaces of the yoke 2, a ainst which it should preferably rest. i set screw 17 threaded through the yoke 2 adjacent the handle 3 at about a 45 angle with the center line of said handle engages the rear face of the I bearing block 12 (which face is normal to the center line of the handle means, displacement of the block 12 circumferentiallyof the crank-pin 9 being oper- I ated on is prevented. The bearing 12preconformityA vents undue entry of the pin 9 toward the bottomor rear of the yoke 2, and also limits the depth of-the bite and cut of the tool 10.

The other bearing-13 at. the leading side of the tool 10 has its bearing surface curved to the radius of the cylindrical pin surface that it engages, and is mounted on the bridge member 4 in a position substantially at a right angle from the tool, so as to bear against the pin 9 along an arc-'whose middle point falls a little below (toward the tool 10 from) a plane through the center of the pinperpendicular to the center line of the tool handle. As shown, the rear face of the block 13 is curved, near its edges, in with the arc-shaped rear inner edges of t e sides of said block shall The curvature radius greater seat and ride on said yoke. of the yoke edges 'is to a than that of the in 9 and about a center a little above the plane its front and rear curved surfaces; and

through the latter perpendicular 'to the center line of the handle 3. Thus the bearing 13 has a wedge form in reference to 1 when it is forced upward circumferentially of the pin 9, its. bearing-surface is thrown anil tilted toward the bottom of the yoke 2 a itt e, pin 9. This circumferential adjustment of the block 13 is efiected, by Ineans of a set screw 21 threaded through 2, lug 22 projecting from the back of said block between the sides of the member; and bearing in a socket or depression'23 in the lower forward corner of the yoke 2. The bearing 13 coacts with the bearings 11 and 12, therefore,

in controlling the position or centering of the frame 1 on the pin 9 by a wedging mounte the member 4, so that so 'as to press harder against the action, and tends to insure more even, uniform, smooth action by the tool 10.

The tool 10, it will be seen, comprises a generall rectangular, oblong block of metal d in a close, snug socket 25 in, the portion of the yoke 2 that mer' s with the handle 3. In order that thetoo 10 and the bearing 11 may be adjusted relatively to one another, the tool is arranged to slide in the socket 25 as a slideway, andis screwed fast on the end of a rod 26 lym' 1n a curved bottomed groove in the hand e 3' and in.

threaded engagement with a cylindrical nut member 27 mounted in a recess near the end of the handle. (See Figs. I and III).

The rod 26 and the tool block 10 are retained in place by a filler member 28 in the groove that is itself mounted on the inner side of a cover plate 29 screwed to the handle 3 over the groove. The nut member 27 has round holes 31 for receiving the end of a rod for turning the nut to adjust the tool.

The active portion of the tool 10 consists of a suitably hardened and tempered metal strip 33 (see Figs. I and IV) dovetailed in an undercut groove across the outer end of the tool block. Thisstrip 33 is so proportioned and arranged that its leading corner 34 is about in the plane of the center line L of the handle 3,which center line L, as shown, also extends through the center of the pin 9 when the bearings 12 and 13 are suitably adjusted, and thus constitutes the center line of the whole appliance in a functional sense. While the top surface 35 of the piece 33 is preferably very nearly perpendicular to the center line L just mentioned, it need not be exactly so, but may be inclined back from the leading edge, towardleading corner may be substantially parallel to the center line aforesaid, or slightly inclined forward therefrom. While the sharp leading corner 34 of the piece 33 may act,

as cutter or scraper if its top surface 35 be plain,-I prefer to groove this top surface 35 (like a file) at an inclination, as shown in Fig. V, so as to secure afile action.-

In Fig. VI, I have illustrated diagrammatically the employment of my appliance in refinishing a crank-pin of an automobile internal combustion engine. As shown, the connecting rod 38 isdisconnected from the crank-pin to be refinished, and the corre-' sponding piston 41 is blocked up in the upper end of its cylinder, so as to keep the connecting rod up out of the way as much as possible. My device having been, applied to the crank-pin as shown, the crank shaft -12, and 13 engaged the very bearing surface of the crank-pin that is being refinished. From Figs. VII and VIII, it will be seen that this is not the case, but that these bearings 11, 12, and 13 are of sufficient width axially to seat and engage on the crank-pin Y beyond (at the sides of) the bearing surface portion thereof that is to be finished or renished, and that the tool edge is of such width (and the corner 34 of such length) that the tool shall engage and act only on the portion of the pin intermediate the portions effectively engaged by the bearings 11, 12, and 13.

As here shown, the bearin s 11, 12, and 13 engage and center the fram 1 on zones of the crank-pin 9 (at either side of the origi- -nally round and normally active wearing portion of the crank-pin) that are usually trued and even finished when the crank-pin is turned up and finished, but are normally outside the zone of wearing contact with the connecting rod bearings and so normally remain inactive and unworn in use. In Fig. VII, where the crank-pin shown has square unfilleted flanges 45 at its ends, these zones comprise simply narrow marginal end portions 46 of the cylindrical part of the crankpin; in Fig. VIII, where the crank-pin has fillets 17 .at its ends, said zones comprise the rounded fillet surfaces. As shown in Fig. VII, the bearing surfaces of the bearing blocks 11, 12 and 13 are on square cornered narrow ridges 18 formed by broad, shallow 'grooves in the bearing blocks, of

slightly less width than the acting part 33 of the tool while in Fig. VIII, the bearing surfaces of the bearing blocks are formed by the beads of round cornered ridges 49. The ridges 48 ,and 49 are shown as of-greater width than the crank-pin zones 46 and 47 which they are intended to engage actively and center on; but this does not interfere with the proper action of the appliance. In a word, therefore,-the tool 10 engages and refinishes only the no rmall active central wearingportion of the pin, intermediate the inactive zones 46, 46 or 17 17 It will be .observed that the bearing blocks 11, 12, and

13 are of such thickness as to fit closely between the finished fiat surfaces of the shoulders or flanges 45 with'only a clearance of one-thousandth of an inch, for example, so that the appliance is guided and kept in just the right position, without end play or wabbling or twisting sidewise. This, of course, helpsin insuring a true cylindrical surface for the refinished crank-pin, regardless of irregular wear or other deformation before refinishing.

Having thus. described my invention, I

claim:

1. A finishing appliance for the round wearing surface of a crank-pin comprising a frame with bearings adapted-to engage the pin only at the sides of the portion thereof to be finished, and a surfacing tool on said frame adapted to engage only the portion of said pin intermediate the aforesaid frame bearings.

2. A finishing appliance for the cylindrical wearing surface of a'crank-pin comprising a frame with bearingsadapted to engage and center the frame on trued but normally inactive zones at either side of the round normally active wearing portion of the crank pin, and a surfacing tool on said frame ada ted to engage and refinish only said norma 1y active wearing portion of said pin intermediate said inactive zones.

3. A crank-pin finishing appliance comprising a'yoke adapted to embrace the pin on three sides and open on the fourth side to permit it to be placed on the pin, and having a bearing for the pin and a surfacing tool opposite one another and adjustable with reference to one another; a bearing for said pin on said yoke at the following side of the tool preventing undue entry of the pin into the yoke and limiting the depth of bite of the tool; and an independently ad-' justable bearing shiftable into a position in the opening of the yoke substantially at a right angle from the tool on the leading side thereof. I

4. A crank-pin finishing appliance comprising a frame with a bearing for the pin and a surfacing tool opposite one another and adjustable with reference to one another, a bearing for said pin on said frame at the following side of the tool independently and positively adjustable with reference to said frame to control the action of the tool, and another bearing for said pin mounted on said frame at the leading side of the tool and adjustable circumferentially of the pin to control the position of the frame thereon by a wedging action.

5. In a crank-pin finishing tool, the combination of a rigid yoke adapted to embrace the pin on three sides and open on the fourth bearing for said pin on-said yoke at the following side of said tool preventing undue entry of the pin into the yoke and limiting the depth of bite-of the tool, said latter bearing being independently and positively adjustable with reference to said yoke; and a tension member secured across the opening opposite said socket; a surfacing tool adjustable in said socket with its leading edge toward the open side of the yoke; a bearing for said pin on said yoke at the following side of said tool preventing undue entry of the pin into the yoke and limiting the depth of blte of the tool, said latter bearing being independently and positively adjustable with reference to said yoke; a bridge member rigidly-secured across the opening of said yoke; and a bearing adjustable on said bridge member at the-leading side of said tool.

In testimony whereof, I have hereunto signed my name at Philadelphia, Pennsyl Vania, this 29th day of November, 1920.

Witnesses: I I

JAMEs H. BELL, v E. L. FULLERTON;

SCIOTA A. NoNsUoH. 

